package com.initialize.pub.token;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.initialize.pub.config.SiteConfig;
import com.initialize.pub.exception.TokenException;
import com.initialize.pub.generate.dao.UserMapper;
import com.initialize.pub.generate.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;
import java.util.Objects;

public class AuthenticationInterceptor implements HandlerInterceptor {
    @Autowired
    UserMapper userMapper;

    @Autowired
    TokenService tokenService;

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
        // 如果不是映射到方法直接通过
        if (!(object instanceof HandlerMethod)) {
            return true;
        }
        HandlerMethod handlerMethod = (HandlerMethod) object;
        Method method = handlerMethod.getMethod();
        //检查是否有passtoken注释，有则跳过认证
        if (method.isAnnotationPresent(PassToken.class)) {
            PassToken passToken = method.getAnnotation(PassToken.class);
            if (passToken.required()) {
                return true;
            }
        }
        //检查有没有需要用户权限的注解
        if (method.isAnnotationPresent(UserLoginToken.class)) {
            UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
            if (userLoginToken.required()) {
                //读取用户的token
                String token = tokenService.getUserToken(httpServletRequest);
                if (token == null) {
                    throw new TokenException("无token，请重新登录");
                }
                if (SiteConfig.FLAG) {
                    //监测是否是测试token
                    if (token.equals(TokenUtil.TOKEN_TEST_TOKEN)) {
                        return true;
                    }
                }
                // 获取 token 中的 user id
                int Id = tokenService.getId(httpServletRequest);
                User user = userMapper.selectByPrimaryKey(Id);
                if (Objects.isNull(user)) {
                    throw new TokenException("参数错误");
                }
                // 验证 token
                JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(user.getPsd())).build();
                try {
                    jwtVerifier.verify(token);
                } catch (JWTVerificationException e) {
                    throw new TokenException("401");
                }
                return true;
            }
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest,
                           HttpServletResponse httpServletResponse,
                           Object o, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest,
                                HttpServletResponse httpServletResponse,
                                Object o, Exception e) throws Exception {
    }
}